...it's not used by mainline or UMC, doesn't overlay or underlay well
with other images, and would basically only be useful for producing
variants of the gohere graphic. This change meands all item/ graphics
have actual uses in mainline.
Genuinely unused ones go to the attic. Where they come from and the
reason they're unused (when that's known) is documented in the attic
README. On this round I discovered that the Dwarvish Explorer
animation sprites that looked unused should have been wired into the
Explorer unit and never were.
None of these are required in either mainline or UMC. The deleted
ones are duplicates of images moved elewhere in the tree; the moved
ones go into the new attic directory for archiving.
